RESUMEN
Purpose The aims of this study were to propose a simple methodology to assess the rinsing volume of syringe extension sets and to compare several marketed devices. Methods A UV-spectrophotometry assay using quinine hydrochloride as drug substitute was developed. Quinine concentration ranged from 20 to 200 µg/ml. The assay was validated with the accuracy profile method and tested on five different assemblies (device+extension sets) with different dead-space volumes (1.28-2.80 ml) and at two different quinine concentrations (0.3 and 8.0 mg/ml). Rinsing was performed stepwise with water for injection until reaching an undetectable quinine concentration. After fitting the data with a Weibull model, assemblies were compared with an ANOVA performed on ranks (GraphPad, La Jolla, USA). Results The within-day and between-day precision ranges were 0.39-0.81 and 0.48-0.84%, respectively. The lower limit of quantification was 4.26 µg/ml. The volume required to completely rinse the infusion line was different according to the initial drug concentration and to the device assessed: from 6 to 10 ml for a low quinine concentration and from 7 to 17 ml for a high quinine concentration. Conclusion This study shows that a simple, cheap and easy-to-use methodology may be used to assess the rinsing volume of syringe extension sets. The rinsing volume is different according to the tested device.